


Undertale One Shots

by GollyGeeJustLilOldMe



Category: Undertale (Video Game)
Genre: Accidental Voyeurism, Cheating, Drunk Sex, Ecto-Genitalia (Undertale), Fontcest, I'm terrible at this, Implied Relationships, M/M, Masturbation, Other, Plot What Plot/Porn Without Plot, Sibling Incest, Tagging I mean, Voyeurism, edgeberry, honeymustard - Freeform, idk - Freeform
Language: English
Status: In-Progress
Published: 2016-12-03
Updated: 2016-12-05
Packaged: 2018-09-06 05:58:38
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 2,332
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8737477
Author URL: https://archiveofourown.org/users/GollyGeeJustLilOldMe/pseuds/GollyGeeJustLilOldMe
Summary: Just some Underale one shots... Mostly fontcest, sanscest and papcest (by mostly I mean only). I'll add tags with updates. Oh and updates at least once a week. Yes I do requests just comment what you wanna see and I'll try and make it happen (no promises though).Also I'm just terrible at tagging I'm so sorry.And sorry if you find any mistakes I'll try and edit those out later.





	1. The Truth Serum (Honeymustard)

They were both drunk off their asses sitting on the floor late at night, their brothers had organized a sleepover with Pap and Cranberry and they decided to get together themselves. For some reason Slim and Classic didn't want to join in on the fun so they thought they should just go ahaid and get drunk on their own.

It is said that alchohol is a truth serum, these guys were living proof of it. One secret after another got spilled out, past mistakes over resets coming out until "i've always wanted to fuck my brother." Strech said suddenly. Red paused, his jaw hanging open in shock. Silence filled the air for a minute until Red began "dude-" but was stopped right away by Strech "nah man nah- can we- can we just like... forget i said anything?" he could regret it even in his drunken state.

"nah man i can relate." when the smaller one said it he couldn't believe it, but then it made sense. They were the ones more alike. "i mean he's just so perfect and i'm so-" Red started "so not." Strech finished. They stared at eachother for ages in the darkness, but then their drunk minds started working "you look so much like him." the red skeleton said, squinting at him through the veil of darkness. "yea you too..." Papyrus continued the thought.

And before another word could be said they smashed their teeth together in a skeletal kiss, tongues quickly summoned an fighting for dominance. This was a fight the smaller one was soon losing and quickly he accepted his role moving down to the forming bulge in the orange skeleton's shorts. His tongue licked all over it through the fabric, helping it shape and harden faster. "oh stars sans." the other moaned as Red slipped off his shorts and let his orange member spring free.

With one hand in his pants stroking his own member and the other on the tallers one's cock, firmly holding it into place he slowly brought his face closer teasingly licking the tip. Papyrus groaned, he hadn't done this in a while and it felt so much better to have someone else do it for him. Especiallly when that someone looked so much like Blue. He moaned at the thought of his brother being here insted of Red and soon his drunken brain could see his brother playing with his dick like it was an orange popsicle.

Red closed his eyes and imagined he was licking his brother's cock like this, slowly he moved to take it all in starting by sucking at the tip and then further inching it into his mouth. "oh yes sans, stars that feels good." the praise made him groan in pleasure while sucking sweetly on the orange member now whole in his mouth. As he felt a hand gently stroke the top of his skul he began bobing his head up and down while pumping his own cock faster.

The feeling of Red's mouth was amazing, his cock thrusthing against those sharp teeth and wet tongue was so good he could feel himself close. And as Red bega speeding up and breathing heavily onto his ecto flesh he felt his tongue slide out. "oh sans i'm so close oh stars i'm gonna-" he gripped the smaller skeletons hear tightly as he came inside his mouth with a loud moan. Soon after finishing he let the other step back and watch as his breath hitched and his hand sped up in his shorts.

Seeing that hungry lustful loom on Papyruses face pushed Red over the edge and he swallowed what was left of his hot creamy cum before he came in his shorts with one last moan. He dropped on his back tired and could hear Strech moving over to him. He laid next to him on the wooden floor, his long bony fingers stroking Red's slightly cum stained face.

"we're fucked up, aren't we?" Strech asked gently kissing the others face and neck. "yea." Sans simply replied.


	2. Date Night (Edgeberry)

When the date ended Fell walked him home with his arm around the small blue Sans and when they finally arrived at the door of the swap brother's house Blue couldn't help sad the night is over already. "I HAD A REALLY GREAT TIME FELL!" he chirped while opening the door.

"I... I'M GLAD. I DID AS WELL."

The house seemed empty and Blue could already guess his brother was with either Classic, Slim or Red.

"WELL GOODBYE I GUESS!" just as Blue was about to go into his house-

Clank.

Their teeth met suddenly into a skeletal kiss which took a bit for them to relax into. Just as Blue was closing his eyes they bolted open and he shivered as he felt something wet brush along his teeth. Fell had summoned a tongue and was gently tracing it along the smaller skeleton's asking for entrence and Sans was more than happy to comply.

Blue opened his mouth and allowed the other to explore and map out every inch of it, licking gently and breathing in Sans' every gasp, before he summoned his own blue tongue. Soon he caught in a hot and messy kiss, he can feel that delicious lounge plunge deep into his mouth, sans can't help but moan at the rough treatment.

Before he could even process what he was doing he had already pulled Fell inside and as they broke off the kiss whit a trail of saliva connecting their mouths they hurried up the stairs into Blue's room. As the little Sans locked the door behind them he turned to see Papyrus sitting on the bed, panting as he took his armour off. Blue blushes and looks away, taking a deep breath and gathering his courage before heading over to the bed.

Papyrus barely has time to spread his legs before the other starts to lick kittenishly at his already glowing crotch through his skinny jeans. The tongue is enough to make the other skeleton ache even more as he lets out a needy whine and shivers from the building pressure in his pants. With shaky hands Fell reaches down to pull out his hard glowing member and grabs himself at the base, stroking a bit to help, but two small hands on his convince him to move his hands. As he lets go Sans starts to tenderly suck at the tip as his tiny hands run over the rest of the other's lenght. Then Sans swallows him whole and the sudden warmth feels so good on his throbing cock.

It's such a dissapointment when Blue stops and let's go of his cock and he hisses at the cold air hitting it.

He shivers as he feels bony hands ghost across his ribs. Soon harsh bites accompany the smooth caresses, bringing Sans the rest of the way and with a tug and a gasp, he can feel his own skeletal erection spring into being. But when Blue climbs into his lap in nothing but a whit teeshirt all of his thought's stop and all he can do is stare at the beautiful small body in front of him. His hands almost seem to move by themselves and ghost across the other's ribs. The smaller skeleton shivers to the smooth caresses and soon feels his own ecto vagina form and he begins to rut against Fell's already leaking cock.

Papyrus' moans grow louder, wrapping his arms around Blue's head, bringing it close to his own. They both panted and moaned as their bodies were pressed together, Sans rested a hand on the talles skeleton's chest, while still grinding against him. Fell soon dived for the little one's neck, kissing it and occasionally biting it teasingly with his sharp teeth. Sans was soon loosing his dominance over the other but was too lost in the pleasurefull licks on his neck to care.

Fell, taking advantage of this, flipped them, laying Sans down on his back and backed away a bit to calm himself and take in the view. Beneath him was a whimpering mess of bones, already dripping wet. "so fucking cute" he muttered under his breath with a chuckle, Blue not even hearing him over the lewd sounds that filled the room. He gently lifted Sans' legs and rested them on his shoulders. "Please..." whispered the other in a soft, pleading voice. "Nyeh. how can I say no?"

Papyrus took a hold of his hard dick and teased the dripping entrence rubbing it around before finally slowly putting it in. "are-Are You Ready?" he asked voice suddenly more stern. The other nodded shyly. Papyrus pulled out before slamming back in, "Fuck! So fucking tight!" he groaned as he started to thrust steadily into him. Sans closed his eyes as he felt Fell's member thrust into him, moaning loudly as the otger went faster. Going further faster Fell eventually found Sans' g-spot, making the other squick and open his eyes, panting hot heavy and breaths.

After another few firm thrusts in that spot Sans felt himself near his climax "I-I Think I'm Gonna-" this made Papyrus speed up, also feeling himself growing closer. With some more hard pounds into Blue they both came, holding eachother firmly. Fell rode through his orgasm, carefully taking himself out of Sans and laying next to him for rest. Only thir panting filled the room before the taller one broke the silence "was... Was That Alright Berry?" he asked, his voice husky and low. The other turned to look at him with a tired yet cheerful smile "Fe That Was Amazing!" he giggled making the other smirk as well.

Suddenly Papyrus shifted and Blue found himself in a tight hug, a skeletal kiss pressed on his head. It was kind of weird at first, Fell didn't really strike him the cuddling type. But hey Sans wasn't complaining really. Before they knew it they had fallen asleep in eachother's arms.


	3. No Skeletons In My Closet (Fellcest ft. Blueberry)

He had never seen his brother happier than when he was with Red. And he had never seen him more heartbroken than when he suspected he was cheating. All he did was lay around in his boxers and tank top all day sleeping so he can stay up and cry at night. It was really getting Blue worried when a week passed and nothing changed. The sad part was he believed in Red, believed with all of his heart he wouldn't hurt his brother. So he decided to find out for sure, he'd look around Red's for any evidence of him cheating and then he could tell Papy with certainty that Red is innocent.

That night he sneaked out and used the machene to get to the Fellverse. Lucky for him the Fell brothers worked late at night so that gave him enough time to sneak into their house and inspect Red's room. Honestly after an hour of searching through all that junk Blue could say the only crime Red had commited was not cleaning his room in surely over a few months. I mean look at this sock, it's basically stone, and not to mention-

"b-boss slow down please! we-we're not even in the house!" they were back home. He must have lost track of time. They were coming up the stairs in a hurry and Blue had no choice but to hide. Quickly he did the first place he saw, panic bluring his mind. The closet. Jumping into it he finds out the door is broken leaving it slightly open, not enough for him to be seen but enough for him to see part of the room through. He heard the door open just as he settled in and to his surprise he heard two voices. What was Fell doing in Red's roo- "o-oh stars b-boss yeah!" then he heard the soft moaning and it was all clear, he didn't even have to see it to know what was going on. But unfortunetly for the little San he knew was in for quite a show when the two edgy skeletons came into sight.

Papy was right, his boyfriend had been cheating on him, and apparently with his own brother. He snapped out of thought as he heard Red get louder, panting harder. When he looked he realised why, while he had been lost in thought the two had already gotten onto the bed and had started fucking. Blue didn't want to look but for some reason he couldn't look away. The smaller red skeleton was on his hands and knees while the other was thrusting into him at a rapid pace, pounding him into the bed. Red moaned and begged as the other huffed and growled answering his pleas by going faster and harder into him.

It started getting too much for Blue, he was starting to feel uncomfortably hot and felt his magic pool in his pants despite him trying to push these feelings down. "a-ah b-boss!" Red's horny moaning and the lewd wet sounds were too much and Berry soon found himself with a hand in his pants steadily pumping his newly formed ecto cock. He focused on the taller one's face, that cocky smirk and slight red flush, his tongue out a little bit as he huffed and groaned. Blue had always had a bit of a crush on Fell to be honest, even now he could picture himself in Red's place as he feels pressure build in his cock, hand moving faster and grip tightening. "b-boss i'm g-gonna-!" the smaller skeleton moaned out "You may." the other one growled and they both came, red magic overflowing the tight ecto pussy "O-oh stars!" Blue couldn't help but gasp as he came, blue sticky cum now covering his hand and pants.

Both brothers turned and were staring at the closet door, at him. Berry paniced and jumped out "b-blue! w-wait!" he could hear Red yell behind him as he stormed out of the room.


End file.
